[bigtrakzapzap]

tl;dr, check these sites:

https://www.wikimatrix.org

http://wiki.c2.com/?TopTenWikiEngines <- origin of the word "wiki" ( http://wiki.c2.com/?WikiWikiWeb )

Having setup the whole Atlassian on-prem SSO suite of apps on Linux with Git and LDAP talking to AD on Windows, it depends on your needs, as there are a variety of different wiki/collaboration solutions with different capabilities. I've also used these:

- Dokuwiki (very simple, text file-based)

- Mediawiki (LAMP / database-backed)

- SharePoint (MS $$)

- Quip

Others to look at (including sometimes CMSes)

- OneNote

- Liferay

- Drupal

- Statamic

- WordPress

Also, Confluence has tons of plugins for customization and can be made to be fast with proper configuration.